The invention relates to a catalyst for producing hydrogen or synthesis gas from a mixed gas containing dimethyl ether and water vapor or carbon dioxide, and a manufacturing method of hydrogen or synthesis gas using the same.
Synthesis gas is composed of carbon monoxide and hydrogen, and has wide applications as a raw material for ammonia synthesis and various chemical products, as well as used directly as a raw material for methanol synthesis, oxo synthesis, Fischer-Tropsch synthesis and the like.
Heretofore, some methods of manufacturing synthesis gas and methods of manufacturing hydrogen utilizing them are known.
For example, there are (1) gasification of coal, (2) steam reforming of hydrocarbon using natural gas, LPG, naphtha or the like as the raw material, (3) partial oxidation of hydrocarbon using natural gas, LPG, naphtha, heavy-duty oil or the like as the raw material, and so on.
However, the above coal gasification of (1) has a problem that a very complex and expensive coal gasification oven is necessary, and the apparatus becomes a large scale plant. The steam reforming of the hydrocarbon of (2) has a problem that a special reforming oven is necessary because of requiring a high temperature of 700 to 1200xc2x0 C. for the reaction to proceed due to its great endothermic reaction, and the catalyst to be used is required to have a high heat resistance. The partial oxidation of the hydrocarbon of (3) has a problem that a special partial oxidation oven is necessary because of requiring a high temperature of 1200 to 1500xc2x0 C., the treatment of a large quantity of soot generated with the reaction proceeding is a problem, and in the case of using a catalyst, the catalyst is deteriorated by the deposition of a large quantity of carbonaceous material on the surface of the catalyst.
An object of the invention is to provide a catalyst and a manufacturing method capable of solving the problems of the above prior art, and obtaining hydrogen or synthesis gas in a high yield at a low temperature.
The inventors investigated eagerly in order to solve the above problems, and as a result, they noted dimethyl ether as the raw material gas. Then, they found that copper, iron, cobalt, palladium, iridium, platinum, rhodium and nickel are very effective as a catalyst for reacting dimethyl ether with water vapor or carbon dioxide to produce hydrogen or synthesis gas, and can produce hydrogen or synthesis gas efficiently at a low temperature to complete the invention.
Thus, the invention relates to a catalyst for producing hydrogen gas from a mixed gas comprising dimethyl ether and water vapor or carbon dioxide gas, which comprises copper, iron, cobalt, palladium, iridium, platinum, rhodium, or nickel as an active component, and a method of producing hydrogen or synthesis gas which comprises contacting a mixed gas comprising dimethyl ether and water vapor or carbon dioxide gas with the above catalyst.